Many plant species, commonly cultivated as food crops, have an irritating sap and/or a coating on their exterior surface to protect the plant from various forms of predation. The presence of this irritant can make harvesting the harvest portion from such a plant an uncomfortable experience. In this context a "harvest portion" is that portion of the plant for which the plant is cultivated, along with an attached section of stem.
Okra is a typical example of the type of plant for which a device embodying the present invention is directed. The harvest portions of the okra plant consist of pods produced at the end of woody stems. The pods project upright.
The exterior surface of the leaves and pods are covered with an irritating film. The sap of the plant is also an irritant to the skin of most people. Both the film and the sap create an itchy, burning sensation in the general area in which they contact the skin surface.
The pods of the okra plant are sometimes harvested by grasping the pod and pulling it free from the plant but such typically causes damage to the pods. In order to properly harvest the pods, the attachment between the stem and the okra pod must be severed. This can be and has been accomplished in the prior art by, for example, reaching within the leafy structure of the plant, manually grasping the pod with one hand, severing the stem, with a device such as a knife or a pair of snips, held in the other, and maintaining physical control of the pod until it is deposited in a basket or other type of device suitable for holding a quantity of the harvested pods.
Severing the stem causes a droplet of sticky sap to form at the tip of the severed stem. Because of the stem's close proximity to other pods, the droplet formed can readily contact the skin of a person harvesting the remaining pods. Contact with the sap of the plant is, therefore, highly likely when harvesting a large quantity of okra pods. Additionally, reaching within the leafy structure of the plant usually results in contact between the irritating film covering the leaves and the skin surface of the person harvesting the pods. Because of the high probability of the skin contacting either the film and/or the sap during the harvesting process, protective measures need to be taken by the majority of people engaged in harvesting okra pods.
Wearing protective clothing, such as long sleeved shirts and gloves, can be an effective protective measure when the harvesting will not continue for an extended period of time. However, after an extended period of harvesting, sweat saturation of the protective clothing can create a path for the irritant to pass through to the skin surface. In order for protective clothing to offer effective protection for an extended period of time, it must provide a moisture proof barrier between the skin and the irritating film and sap. However, this is an impractical solution in the hot, humid conditions under which the plants are typically grown and harvested.
A better solution for minimizing contact between the film and/or sap is to use a harvesting device which allows the worker, at a distance from the plant, to preferably indirectly grasp the pod, sever the stem, and maintain control of the pod until it is deposited at a desired location. While this solution minimizes contact with the irritating film and sap, current methods of maintaining control of the pod after the stem is severed increase the risk of losing and/or damaging the pods during harvesting.
A current method of maintaining control of the pod after the stem is severed is severing the stem while the pod is within a containment vessel which is sealable by an extended severing blade. The severing blade, dimensioned to allow the blade to provide a barrier across the opening, maintains the pod within the containment vessel until the blade is retracted. A problem with this method is the loss of pods from the containment vessel when the blade is retracted to harvest another pod. There is nothing to prevent a pod supported by the blade from falling from the containment vessel once the blade is retracted. Since the operator may not see the pod fall or may not wish to retrieve the pod from its landing place, this can lead to the loss of available harvest portions.
Another method of maintaining control of the pod after the stem is severed uses a forked member which pierces the pod to hold it in place during the stem severing process. The fork remains in place until the pod is released at the desired location. This piercing damages the pod and renders the pod unsuitable for sale in markets.
Although the use of harvesting devices is a better method than wearing protective clothing when harvesting for an extended period of time, their use can increase damage to and loss of available harvest portions.
It is desirable, therefore, to have a harvesting apparatus which will maintain control of the harvest portion after the stem is severed without piercing the harvest portion or temporarily blocking its exit from the containment vessel by an intermittent barrier.